Integral image elements which use a lenticular lens sheet or a fly's eye lens sheet, and a three-dimensional integral image aligned with the sheet, so that a user can view the three-dimensional image without any special glasses or other equipment, are known. Such imaging elements and their construction, are described in "Three-Dimensional Imaging Techniques" by Takanori Okoshi, Academic Press, Inc., New York, 1976. Integral image elements having a lenticular lens sheet (that is, a sheet with a plurality of adjacent, parallel, elongated, and partially cylindrical lenses) are also described in the following Unites States patents: U.S. Pat. No. 5,391,254; U.S. Pat. No. 5,424,533; U.S. Pat. No. 5,241,608; U.S. Pat. No. 5,455,689; U.S. Pat. No. 5,276,478; U.S. Pat. No. 5,391,254; U.S. Pat. No. 5,424,533 and others; as well as allowed U.S. patent application Ser. No. 07/931,744. Integral image elements with lenticular lens sheets use interlaced vertical image slices which, in the case of a three-dimensional integral image, are aligned with the lenticules so that a three-dimensional image is viewable when the lenticules are vertically oriented with respect to a viewer's eyes. Similar integral image elements, such as described in U.S. Pat. No. 3,268,238 and U.S. Pat. No. 3,538,632, can be used to convey a number of individual two-dimensional scenes (such as unrelated scenes or a sequence of scenes depicting motion rather than one or more three-dimensional images.
Integral image elements using reflective layers behind the integral image to enhance viewing of the integral image by reflected light, are also described in U.S. Pat. No. 3,751,258, U.S. Pat. No. 2,500,511, U.S. Pat. No. 2,039,648, U.S. Pat. No. 1,918,705 and GB 492,186. While various types of reflecting layers are described in the foregoing, none of those references attaches any particular importance to the characteristics of the reflective layer nor suggests how such characteristics might affect image quality seen by a viewer.
Also, previous lenticular imaging methods typically used a method for exposing the images through the lenticular material. This causes flair because multiple views must be exposed and each view introduces a background flair into the overall scene due to light scatter from the lenticular material. Resolution is also lost because the lenticular material does not have as high an optical resolution as is necessary for high quality imaging and as a consequence resolution is lost during the exposure of the image. In U.S. Pat. No. 5,276,478 a method is described where the light sensitive layer is exposed with light from behind the back surface rather than through the lenticular lens sheet. However, undesirable halation problems with subsequent reduction in image quality, could be caused by light which passes through the light sensitive layer and is reflected back to it from the front surface of the lens sheet.
Japanese published patent application JP 4097345 describes the use of an anti-reflection layer on the surface of the lenticules as well as an anti-halation or anti-reflection layer on opposite side from the lenticules. However, the light sensitive layer is exposed through the lenticules. The lenticule side anti-reflective layer appears intended to reduce scattering of light from the lenticule side during that type of exposure. The opposite side anti-halation layer uses dyes which are removed by processing solutions which must pass through the light sensitive emulsion layer to effect dye removal. U.S. Pat. No. 1,817,963 describes a color photography technique using a dye on lenticules. However, the color "film" is intended for exposure in a camera with the lenticules facing the lens.
It would be desirable then, to provide an integral image element for viewing by reflective light, which has a reflective layer of defined properties which allows the image to be readily viewed while still maintaining good image quality perceived by the viewer. It would also be desirable in making such an element, to produce a high quality integral image element by using a method of exposing a light sensitive layer on the back side of an integral lens sheet from behind the light sensitive layer so as to produce low flair and high resolution, which method also results in low halation. It would also be desirable for many applications, to provide an integral image element with good contrast of the image being viewed.